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Re: question regarding OCMIP-2 CO2 code



Chris,

This isn't a problem, more of a question. I am building a correspondence
between the notation from the README associated with your code and the
abiotic HOWTO. The two main questions concern the formula for the net
carbon flux and taking air pressure into account. I wanted to make sure
that I my understanding is correct.

The abiotic HOWTO gives the air-to-sea flux of carbon as (eqn 4a)
F = Kw (Csat - Csurf), where
Kw is the gas transfer velocity (including sea-ice fraction term) [m/s],
Csat is the saturation concentration [mol/m^3], and
Csurf is aqueous concentration of CO2 [mol/m^3], which I assume is CO2*.

The README associated with your code gives the air-to-sea flux as
Flux = kw/K0 * delta CO2*.

Please correct me if I am wrong on what follows.

delta CO2* (= co2*air - co2*water) is in mol/kg, differing by a density
factor from the (Csat - Csurf) of the abiotic HOWTO.

>From the README, the ratio kw/K0 has units
mass/(area*time) = mass/vol * len/time.

Is it correct that the kw/K0 of the README is rho*Kw from the abiotic
HOWTO?

Concerning air pressure, in the abiotic HOWTO,
Csat (= alphaC * pCO2atm * P/P0) explicitly takes it into account. The
corresponding term in the README is co2starair, and it does not appear to
me to take pressure into account. It is my understanding from reading
over the old mailing list posts that it was decided to include air
pressure for CO2. I understand that this happened after your code was
posted. To include air pressure should co2starair be given by
xco2*ff*P/P0?

Thanks for your time,
Keith

***********************************************************************
Keith Lindsay                              phone: 303-497-1722
Climate and Global Dynamics                fax:   303-497-1700
National Center for Atmospheric Research   email: klindsay@cgd.ucar.edu
P.O. Box 3000
Boulder, CO  80307-3000

On Fri, 19 Feb 1999, Chris Sabine wrote:

> Hi Keith,
> 	We will try to fix the code on our end so others don't run into
> this problem too. Let us know if you come across any other problems.
> 
> Thanks,
> Chris
> 






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